Teenager Mika Stojsavljevic underlined her potential by becoming only the fifth British youngster to reach the US Open junior final.
The 15-year-old Londoner won 6-0 3-6 6-3 in her girls’ semi-final against American third seed Iva Jovic on Friday.
Stojsavljevic could have been involved in an all-British final against 16-year-old Mimi Xu, with whom she reached the Wimbledon girls’ doubles final in July.
But eighth seed Xu, from Wales, lost 6-4 6-4 to Japanese seventh seed Wakana Sonobe in the other semi-final.
Stojsavljevic is the first British girl to make the New York final since Heather Watson’s victory there in 2009.
Andy Murray won in 2004 before Oliver Golding beat compatriot Liam Broady in the 2011 boys final.
Scottish teenager Charlie Robertson, who has been mentored by former world number one Murray, could not emulate their achievement after losing in the boys’ singles semi-finals.
The 17-year-old was beaten 6-3 6-3 by Norwegian top seed Nicolai Budkov Kjaer.